David heston



(N0 Mdelz) 2' Sheets-Sheet i DHESTON. y v

KEY LOCKING MEGHANISM POR TYPE WRITING MACHINES.

,033'. Patented July 14, 1891.

ATTO R N EV.

INVENTOR:

(No Model.)

AD.. BEST-0N. KEY LOCKING MEGHANISM FOR TYPE 'WRITING MAUHINES. No; 456,033.

INVENTOR:

Patented July 14, 1891*.

UNITED STATES PATENT OEEICE.

DAVID HESTON, OF PIIILADELPHIA, PENNSYLVANIA, ASSIGNOR TO WYOKOFF, SEAMANS da BENEDICT, OF NEW YORK, N. Y.

KEY-LOCKING MECHANISM FOR TYPE-WRITING MACHINES.

SPECIFICATION forming part of Letters Patent No. 456,033, dated July 14, 1891.

Application iled July 20, 1889.

and county of Philadelphia, State of Pennsyl- Vania, have invented a new and useful Improvement in Type-Vriting Machines, which improvement is fully set forth in the following specification and accompanying drawings.

My invention consists of an attachment to type-writing machines, whereby the entire system of keys may be securely locked when the last letter which can be printed or written upon a line has been struck, so that a further impression cannot be made by the type of said last letter, and blurring or blotting of the same thereby prevented.

Figure 1 represents a rear elevation of part of a type-writing machine embodying my invention. Fig. 2 representsa perspective view of the same, showing my attachment applied thereto. views of another form of a type-writing machine,showing my improved attachment in two positions.

Similar letters of reference indicate corresponding parts in the several figures.

Referring to the drawings, A designates the frame of a type-writing machine, having a carriage B thereon, to which is attached a ratchet-bar O, engaged by a feeding mechanism D, having a rocking support E. The said support is attached to a cross-bar F, upon which rests the spacing-bar and key-levers. The parts thus far described are Well known in the art; and my improved attachment, as shown in Figs. 1 and 2, consists of a lever G, pivoted to the frame A or to an ear depending therefrom and havingalower toe or analogous projection H. An arm or stop .I is secured directly to the carriage B or to the ratchet-bar C thereof, as shown in Figs. 3 and 4, and adapted to engage with the lever G.

As shown in Figs. l and 2, the lever G is mounted in a vertical position and disengages itself from the feed mechanism by gravity, and in Figs. 3 and 4 said lever is forced out vof engagement with the feed mechanism by Figs. 3 and 4 represent perspective Serial No. 318,137. (No model.)

the action of a spring K impinging thereagainst.

As shown, the arm or stop J may be either in the form of an angular arm or a post or any similar construction, the object sought being to provide the carriage B or its ratchetbar O with a device to contact with the lever on the frame A. During the last spacing movement made by the carriage B at the end of a printed or written line the stop or arm .I on said carriage is brought into contact with the upper end of the lever G on the frame A. This operation causes the lower end of the said lever G to engage the lower part of the support of the feed mechanism or to bear against one of the arms of said mechanism and lock the same in such a manneras to entlrely obstruct its further rocking or swinging motlon. As this takes place when the last key depressed returns to its normal position, further depression of any one or all of the keys is prevented, and consequently the latter must all remain iirmlylocked until the carriage is run back for another line, when they are all again instantly released.l

The blurring or blotting of the last letter or character of a line is obviated by the attachment, thereby saving time and labor of erasure and avoiding an uncleanly appearance of the sheet operated upon.

Itis well known that when a key-lever or spacing-bar is depressed the bar F is lowered, whereby motion is imparted to the rocking device E, and consequently to the feeding mechanism, this feature, however, broadly considered, being heretofore in use.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. In a type-writing machine, a frame, a vibrating device having a feeding-pawl and provided with a projecting portion, a carriage having a rack adapted to be engaged by said pawl of the vibrating device, combined with a stop or arm attached to said carriage, and a lever attached to said frame and arranged to be moved by said stop so as to engage the said projecting portion of the vibrating device to lock the latter against movement, substantially as described.

2. In a type-Writing machinehe freine A,

5 with the lever G, having Jehe angulaiportion H pivoted thereto, the carriage B, with rack C and depending stop J, the latter adapted to Contact With Jhe one end of the lever G, and

the rocking support E,witl1 pawl D, the said support adapted to be engaged by the projee- Io Lion H of the lever G, said parts being combined substantially as described.

DAVID I-IESTON. Witnesses: Y

JOHN A. WIEDERSHEIM, L. JENNlNGs. 

